In telecommunications, several types of printed monopole antennas are known. Typically, these antennas are fabricated by etching the antenna element pattern in a metal trace bonded to an insulating dielectric substrate with a metal layer bonded to the opposite side of the substrate which forms a groundplane. Printed monopole antennas are also relatively inexpensive to manufacture and design because of the simple 2-dimensional physical geometry. They are usually employed at UHF and higher frequencies because the size of the antenna is directly tied to the wavelength at the resonance frequency.
Geometries of ultra wide band (UWB) antennas, having a bandwidth of at least 25% of the center frequency, have to date generally been based on simple geometric elements, such as rectangles (H. D. Chen, J. N. Li and Y. F. Huang, “Band-notched ultra-wideband square slot antenna,” Microwave and Optical Technology Letters, vol. 48(12), pp. 2427-2429, December 2006), circles (J. Liang, C. C. Chiau, X. Chen and C. G. Parini, “Study of a printed circular disk monopole antenna for UWB systems,” IEEE Trans. Antennas & Propag., vol. 53(11), pp. 3500-3504, November 2005), or ellipsis (E. S. Angelopoulos, A. Z. Anastopoulos, D. I. Kaklamani, A. A. Alexandridis, F. Lazarakis and K. Dangakis, “Circular and elliptical CPW-fed slot and microstrip-fed antennas for ultrawideband applications,” IEEE Antennas Wireless Propag. Lett., vol. 5, pp. 294-297, 2006) or even a combination of these (Z. N. Chen, M. J. Ammann, X. Qing, X. H. Wu, T. S. P. See and A. Cai, “Planar antennas: Promising solutions for microwave UWB applications,” Microwave Magazine, vol. 7(6), pp. 63-73, December 2006).
Other shapes are also known (T. Karacolac and E. Topsakal, “A double-sided rounded bow-tie antenna (DSRBA) for UWB communication,” IEEE Antennas Wireless Propag. Lett., vol. 5, pp. 446-449, 2006.)
Existing designs are, however, difficult to adjust as the parameters are confined by the geometrical constrains of a circular or elliptical disk and the difficulty of combining simple geometric elements.